I had playmates as a child and sought to be included in groups while in school. Since graduating college, however, I have not pursued any social relationships. I spend time with my family and occasionally participate in activities with people who consider me a friend (mostly co-workers or former co-workers), but the desire to join does not come from me.
When I do join in it is usually because I understand it is expected of me and I don't wish to disappoint, or hurt the feelings of those people who are, in whatever way, important to me.
I don't doubt that I would enjoy having someone with whom I could share my interests, but I do not feel capable of the reciprocity required in a relationship that would require me to show interest in their other interests and activities.
Also, as stated by someone earlier, after spending all day working (in hellish customer service roles) my only desire is to completely isolate myself.
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Those who cannot tell what they desire or expect, still sigh and struggle with indefinite thoughts and vast wishes. - Emerson
Selfishness is not living as one wishes to live, it is asking others to live as one wishes to live. - Oscar Wilde